From 2dab4515fb51559b8532633ab7f02c188c81ccb8 Mon Sep 17 00:00:00 2001
From: Andy Killorin <37423245+Speedy6451@users.noreply.github.com>
Date: Tue, 31 Dec 2024 11:20:45 -0500
Subject: [PATCH] conversion to 0RGB

---
 decoder/src/lib.rs | 14 ++++++++++++--
 1 file changed, 12 insertions(+), 2 deletions(-)

diff --git a/decoder/src/lib.rs b/decoder/src/lib.rs
index 1e86c72..ad0f27c 100644
--- a/decoder/src/lib.rs
+++ b/decoder/src/lib.rs
@@ -1,6 +1,6 @@
 use std::{mem::transmute, net::{self, SocketAddr}, slice, sync::{Mutex, OnceLock}};
 
-use openh264::decoder::Decoder;
+use openh264::{decoder::Decoder, formats::YUVSource};
 
 #[no_mangle]
 pub extern fn add(a: u64, b: u64) -> u64 {
@@ -25,6 +25,8 @@ pub extern fn reset_decoder() -> u64 {
 #[no_mangle]
 /// decode h264 packet of given length
 ///
+/// image format is 0RGB
+///
 /// returns 1 if the packet contained a new frame, otherwise 0
 pub extern fn decode_h264(image: &mut u32, packet: &u8, length: u32) -> u64 {
     let decoder = DECODER.get_or_init(|| Mutex::new(Decoder::new().unwrap()));
@@ -34,7 +36,15 @@ pub extern fn decode_h264(image: &mut u32, packet: &u8, length: u32) -> u64 {
     let image: &mut [u8; 4*320*240] = unsafe{transmute(image)};
 
     if let Ok(Some(frame)) = decoder.decode(packet) {
-        frame.write_rgba8(image);
+        let mut buf = [0u8; 3*320*240];
+        frame.write_rgb8(&mut buf);
+        // 0RGB conversion, avoids need to modify openh264
+        for (buffer, image) in buf.chunks_exact_mut(3).zip(image.chunks_exact_mut(4)) {
+            image[1] = buffer[0];
+            image[2] = buffer[1];
+            image[3] = buffer[2];
+        }
+
         return 1;
     }